Lub multimeter tsuas tuaj yeem ntsuas qhov tsis kam ntawm cov conductors thiab cov shaker tsuas tuaj yeem ntsuas qhov tsis kam ntawm insulators
Lub multimeter tuaj yeem ntsuas qhov tsis kam ntawm cov conductors, tab sis tsis yog qhov tsis kam ntawm insulators. Tsuas yog tus shaker tuaj yeem ntsuas qhov tsis kam ntawm insulators. Cia kuv tham vim li cas?
Tus neeg xyuas pib / Insulator
Tus neeg xyuas pib: ib yam khoom siv hluav taws xob zoo
Insulator: ib yam khoom uas tsis zoo hluav taws xob conductivity (ceeb toom, tsis yog ib yam khoom uas tsis muaj hluav taws xob)
Cov conductors ntau hauv peb lub neej yog: tooj liab, hlau, txhuas, kub, nyiaj, graphite, thiab lwm yam.
Cov insulators feem ntau hauv peb lub neej muaj xws li: yas, roj hmab, iav, ceramics, dej ntshiab, huab cua, ntau yam roj ntxhia ntuj, thiab lwm yam.
Qhov peb yuav tsum tau xyuam xim tshwj xeeb rau ntawm no yog qhov insulator yog ib yam khoom uas tsis zoo conductivity, tsis yog ib yam khoom uas tsis muaj hluav taws xob. Hais lus nruj me ntsis, tsis muaj ib yam dab tsi uas yog ib yam khoom uas tsis yog tus coj. Piv txwv li, cov yas yuav tawg ntawm qhov kub thiab txias thiab yog li ua hluav taws xob. Yog li ntawd, cov insulators tau muab faib ua tsib qib raws li qhov kub thiab txias: Y, A, E, B, F, H, thiab C.
Tsis tas li ntawd, cov insulators tuaj yeem tawg ntawm cov hluav taws xob ntau dua thiab ua cov khoom siv hluav taws xob. Yog li ntawd, txawm tias ib qho hluav taws xob ua hluav taws xob yog txheeb ze rau qee qhov hluav taws xob, thiab qhov hluav taws xob no hu ua qhov ntsuas hluav taws xob ntawm lub insulator.
Kev hais lus, txawm hais tias cov hlau raug hlawv lossis tsis muaj qhov cuam tshuam nrog qhov voltage. Tom qab ntawd vim li cas nws tseem yuav tsum tau kos lub ntsuas hluav taws xob? Qhov no yog vim hais tias cov rwb thaiv tsev nyob rau sab nraud ntawm cov hlau muaj ib tug voltage withstand ntau yam. Peb tuaj yeem nkag siab yooj yim tias thaum dej siab tshaj qhov kev coj tus kheej ntawm cov yeeb nkab dej, cov yeeb nkab dej yuav raug puas tsuaj thiab cov dej sab hauv yuav raug txau. Ib yam li ntawd, thaum qhov hluav taws xob ntawm cov xaim hluav taws xob ntau tshaj qhov kev zam ntawm cov rwb thaiv tsev, cov rwb thaiv tsev ntawm cov xaim yuav raug rhuav tshem, thiab tam sim no yuav tawm los, feem ntau hu ua "tawg".
Multimeters thiab Megohmmeters
Kev ntsuas kev tiv thaiv nrog lub multimeter yog siv Ohm txoj cai. Peb txhua tus paub tias thaum lub multimeter ntsuas tsis kam, 1.5V thiab 9V roj teeb hauv lub ntsuas hluav taws xob. Thaum ob qhov kev xeem coj mus txuas nrog lub resistor, qhov tam sim no nyob rau hauv lub 'meter' pib los ntawm tus ncej zoo ntawm lub roj teeb, ces dhau los ntawm lub 'meter' lub taub hau, lub resistor, thiab ces rov qab mus rau lub negative ncej ntawm lub roj teeb. Qhov loj ntawm qhov tsis kam tuaj yeem txiav txim raws li qhov loj me ntawm lub taub hau 'meter', vim tias qhov hluav taws xob tsis tu ncua, thiab qhov loj ntawm qhov tam sim no nyob ntawm qhov loj ntawm qhov tsis kam.
Qhov no yog qhov zoo kawg nkaus rau kev ntsuas qhov tsis kam ntawm cov conductors, tab sis tsis yog rau ntsuas cov insulators, vim hais tias seb lub insulator ua hluav taws xob nyob ntawm qhov voltage thiab kub. Piv txwv li, ib qho insulator tsis yog-conductive ntawm 9V, ces thaum ntsuas nrog ib tug multimeter, ib txwm yuav tsis muaj tam sim no dhau los ntawm lub taub hau ' meter ', yog li qhov tso tawm tsis muaj nqi yog infinite. Tab sis yog tias koj txuas ntxiv siv qhov hluav taws xob ntau dua, nws yuav tawg thiab ua hluav taws xob. Yog li ntawd, thaum ntsuas seb lub insulator yog conductive, ib tug voltage yuav tsum tau teev.
Muaj ib lub tshuab hluav taws xob DC tes ua hauv megohmmeter, thiab cov zis hluav taws xob ntawm lub tshuab hluav taws xob kuj txawv raws li qib voltage ntawm megohmmeter. Lub 250V megohmmeter tuaj yeem tso tawm DC voltage ze li ntawm 250V, 500V megohmmeter tuaj yeem tso tawm DC voltage ze li ntawm 500V, thiab 1000V megohmmeter tuaj yeem tso tawm DC voltage ze li ntawm 1000V... Yog tias koj siv 500V megohmmeter los ntsuas qee yam rwb thaiv tsev tsis kam ntawm cov hlau yog simulated nyob rau hauv 500V DC voltage los ntsuas seb cov hlau yog to.
Yog hais tias ib txoj kab tsis xau nyob rau hauv qhov ntsuas ntawm 500V los ntawm megohmmeter, ces yuav tsis muaj leakage nyob rau hauv qhov voltage ntawm 300V. Yog li ntawd, thaum peb xaiv ib tug megohmmeter rau kev ntsuas, peb yuav tsum xyuas kom meej tias qhov voltage theem ntawm lub megohmmeter yog siab tshaj qhov tseeb voltage ntawm kab. Tsis tas li ntawd, lub megohmmeter tso tawm ncaj qha tam sim no, thaum siv 220V feem ntau yog hloov tam sim no, thiab tus nqi siab tshaj ntawm 220V hloov tam sim no tuaj yeem ncav cuag 220 * 1.414=311V. Yog li ntawd, peb yuav tsum xaiv 500V megohmmeter thaum ntsuas qhov rwb thaiv tsev ntawm AC 220V kab.
Megohmmeter voltage xaiv
Rau cov khoom siv hluav taws xob thiab cov kab uas muaj qhov ntsuas hluav taws xob qis dua 220V (xws li 110V, 48V, 36V, 24V, thiab lwm yam), feem ntau siv 250V megohmmeter;
Rau cov khoom siv hluav taws xob thiab cov kab uas muaj qhov ntsuas hluav taws xob ntawm 220V, 500V megger feem ntau yog siv;
Rau cov khoom siv hluav taws xob thiab kab nrog qhov ntsuas hluav taws xob ntawm 380V, 1000V megger feem ntau yog siv;
Rau lub raj mis porcelain, insulators, thiab lwm yam, feem ntau yog siv 2500V megger;
